Current practice

Most computer accouterments uses SI prefixesdefn. 1 to accompaniment accommodation and ascertain added achievement ambit such as abstracts rate. Main and accumulation memories are notable exceptions.

Main anamnesis and accumulation anamnesis universally use accepted bifold prefixesdefn. 4 to accompaniment capacity.8283848586 On the added hand, beam memory, like that begin in solid accompaniment drives, uses SI prefixesdefn. 1 to accompaniment capacity.citation needed

With a few exceptions, a lot of operating systems and added software abide to use the accepted bifold prefixes in displays of memory, deejay accumulator capacity, and book size, but SI prefixesdefn. 1 in added areas such as arrangement advice speeds and processor speeds.

In the afterward subsections, unless contrarily noted, examples are aboriginal accustomed application the accepted prefixes acclimated in anniversary case, and again followed by estimation application added characters area appropriate.

editOperating systems

Prior to the absolution of Macintosh Arrangement Software (1984), book sizes were about appear by the operating arrangement after any prefixes.citation needed Today, a lot of operating systems address book sizes with prefixes.

The Linux atom uses bifold prefixes if booting up.8788 However, abounding Unix-like arrangement utilities like the ls command, use admiral of 1024 adumbrated as KB/MB (customary bifold prefixes).

The Ubuntu GNU/Linux administration uses the IEC prefixes for base-2 numbers as of the 10.10 release.8990

Microsoft Windows letters book sizes and deejay accessory capacities application the accepted bifold prefixes or, in a "Properties" dialog, application the exact amount in bytes.

Since Mac OS X Snow Leopard, Apple's Mac OS X letters sizes application SI decimal prefixes (1 MB = 1,000,000 bytes).9192

editSoftware

As of February 2010, a lot of software does not analyze symbols for bifold and decimal prefixes.defn. 3 The IEC bifold allotment assemblage has been adopted by a few, but this is not acclimated universally.

One of the declared goals of the addition of the IEC prefixes was "to bottle the SI prefixes as actual decimal multipliers."71 Programs such as fdisk/cfdisk, parted, and apt-get use SI prefixes with their decimal meaning.

GNOME's allotment editor uses IEC prefixes to affectation allotment sizes. The absolute accommodation of the 120×109 byte deejay is displayed as "111.79 GiB"

GNOME's arrangement adviser uses IEC prefixes to appearance anamnesis admeasurement and networking abstracts rate.

BitTornado uses accepted SI prefixes for abstracts ante and IEC prefixes for book sizes

Deluge (BitTorrent client) uses IEC prefixes for abstracts ante as able-bodied as book sizes

Linux's fdisk uses accepted SI prefixes to affectation a 160×109 byte deejay as "160.0 GB"

Example of the use of IEC bifold prefixes in the Linux operating arrangement announcement cartage aggregate on a arrangement interface in kibibytes (KiB) and mebibytes (MiB), as acquired with the ifconfig utility:

eth0 Link encap:Ethernet HWaddr 00:14:A0:B0:7A:42

inet6 addr: 2001:491:890a:1:214:a5ff:febe:7a42/64 Scope:Global

inet6 addr: fe80::214:a5ff:febe:7a42/64 Scope:Link

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

RX packets:254804 errors:0 dropped:0 overruns:0 frame:0

TX packets:756 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:18613795 (17.7 MiB) TX bytes:45708 (44.6 KiB)

Software that uses accepted SI prefixes for admiral of 1000, but not IEC bifold prefixes for admiral of 1024, includes:

Mac OS X v10.6 and after for harder drive and book sizes9394

Software that uses IEC bifold prefixes for admiral of 1024 and uses accepted SI prefixes for admiral of 1000 includes:

GNU Core Utilities95

Flyspray96

bugs.mysql.com97

GParted98

DFSee99

disktype100

raidutil101

FreeDOS-32102

ifconfig103

GNOME Network104

SLIB105

Cygwin/X106

HTTrack107

Pidgin (IM client)108

Deluge109

zFTPServer110

yafc111

tnftp112

WinSCP113

MediaInfo114

editComputer hardware

As of February 2010, no examples of accouterments marketed application IEC bifold prefixes accept been found. Even accouterments types that use powers-of-1024 multipliers, such as memory, abide to be marketed with accepted bifold prefixes.

editComputer memory

The 536,870,912 byte (512×220) accommodation of these RAM modules is declared as "512 MB" on the label.

Measurements of a lot of types of cyberbanking anamnesis such as RAM, ROM are accustomed application accepted bifold prefixes (kilo, mega, and giga). This includes some beam memory, like EEPROMs. For example, a "512 megabyte" anamnesis bore is 512×220 bytes (512×1048576, or 536870912).

JEDEC Solid Accompaniment Technology Association, the semiconductor engineering acclimation physique of the Cyberbanking Industries Alliance (EIA), continues to cover the accepted bifold definitions of kilo, mega and giga in their Terms, Definitions, and Letter Symbols document,65 and uses those definitions in after anamnesis standards6667686970 (See aswell JEDEC anamnesis standards.)

Many computer programming tasks advertence anamnesis in agreement of admiral of two because of the inherent bifold architecture of accepted accouterments acclamation systems. For example, a 16-bit processor annals can advertence at a lot of 65,536 items (bytes, words, or added objects); this is calmly bidding as "64K" items. An operating arrangement ability map anamnesis as 4096-byte pages, in which case absolutely 8192 pages could be allocated aural 33554432bytes of memory: 8K (8192) pages of 4 kilobytes (4096) anniversary aural 32 megabytes (32 MiB) of memory.

editHard deejay drives

All harder deejay drive manufacturers accompaniment accommodation application SI prefixes.defn. 1115

editFlash drives

USB beam drives, flash-based anamnesis cards like CompactFlash or Secure Digital, and flash-based SSDs use SI prefixes;defn. 1 for example, a "256 MB" beam agenda provides at atomic 256 actor bytes (256000000), not 256×1024×1024 (268435456).40 These accessories usually physically accommodate the bifold capacities, but some amplitude is aloof for centralized functions of the beam drive. In added words, there are physically 256×1024×1024 bytes of accumulator on a archetypal "256 MB" beam drive, but some amplitude is bare for functions like abrasion leveling. In the case of a "256 MB" beam drive, the architect can admeasure about 12 MB to centralized functions, and still accommodate 256 actor accessible bytes.

editFloppy drives

Floppy disks accept existed in abundant concrete and analytic formats, and accept been sized inconsistently. In part, this is because the end user accommodation of a authentic deejay is a action of the ambassador hardware, so that the aforementioned deejay could be formatted to a array of capacities. In abounding cases, the media are marketed after any adumbration of the end user capacity, as for example, DSDD, acceptation double-sided double-density.

The endure broadly adopted diskette was the 3½ inch top density. This has a formatted accommodation of 1474560 bytes or 1440 KB (1440×1024, application "KB" in the accepted bifold sense). These are marketed as "HD", or "1.44 MB" or both. This case defines a "third megabyte" of 1000×1024.

Most operating systems affectation the accommodation application "MB" in the accepted bifold sense, consistent in a affectation of "1.4 MB" (1.40625 MB). Some users accept noticed the missing 0.04 MB and both Apple and Microsoft accept abutment bulletins apropos to them as 1.4 MB.35

The beforehand 1200 KB (1200×1024) 5¼ inch diskette awash with the IBM PC AT was marketed as 1.2 MB (1.171875 MiB). The better 8 inch diskette formats could accommodate added than a megabyte, and the capacities of those accessories were generally anyhow defined in megabytes, aswell after controversy.

Older and abate diskette formats were usually articular as an authentic amount of (binary) KB, for archetype the Apple Deejay II declared as 140KB had a 140×1024 byte capacity, and the aboriginal "360KB" bifold sided, bifold body deejay drive acclimated on the IBM PC had a 360×1024 byte capacity.

In abounding cases diskette accouterments was marketed based on unformatted capacity, and the aerial appropriate to architecture sectors on the media would abate the nominal accommodation as able-bodied (and this aerial about assorted based on the admeasurement of the formatted sectors), arch to added irregularities.

editOptical discs

The capacities of a lot of optical disc accumulator media like DVD, Blu-ray Disc, HD DVD and magneto-optical (MO) are accustomed application SI decimal prefixes. A "4.7 GB" DVD has a nominal accommodation of about 4.38 GiB.37 However, CD capacities are consistently accustomed application accepted bifold prefixes. Thus a "700 MB" (or "80 minute") CD has a nominal accommodation of about 700 MiB (approx 730 MB).36

editTape drives and media

Tape drive and media manufacturers use SI decimal prefixes to analyze capacity.116

editData manual and alarm rates

Certain units are consistently acclimated with SI decimal prefixes even in accretion contexts. Two examples are hertz (Hz), which is acclimated to admeasurement the alarm ante of cyberbanking components, and bit/s, acclimated to admeasurement abstracts manual speed.

A 1 GHz processor receives 1000000000 alarm ticks per second

A complete book sampled at 44.1 kHz has 44100 samples per second

A 128 kbit/s MP3 beck consumes 128000bits (16 kilobytes, 15.6 KiB) per second

A 1 Mbit/s Internet affiliation can alteration 1000000bits per additional (125000 bytes per additional ≈ 122 KiB/s, bold an 8-bit byte and no overhead)

A 1 Gbit/s Ethernet affiliation can alteration 1000000000bits per additional (125000000 bytes per additional ≈ 119 MiB/s, bold an 8-bit byte and no overhead)

A 56k modem transfers 56000 $.25 per additional ≈ 6.8 KiB/s.

Bus alarm speeds and accordingly bandwidths are both quoted application SI decimal prefixes.

PC3200 anamnesis on a bifold abstracts amount bus, appointment 8 bytes per aeon with a alarm acceleration of 200 MHz (200000000cycles per second) has a bandwidth of 200000000×8×2 = 3200000000bytes/second = 3.2 GB/s (about 3.0 GiB/s).

A PCI-X bus at 66 MHz (66000000cycles per second), 64 $.25 per transfer, has a bandwidth of 66000000transfers/second×64bits/transfer = 4224000000bits/second, or 528000000bytes/second, usually quoted as 528 MB/s (about 503 MiB/s).

editWebsites and government agencies

The UK government117

The Pirate Bay118

Ars Technica119

Anandtech120